The Jackson Laboratory

Getting Started

Education: Genotyping MiniCourse

This MiniCourse is an introduction to all things genotyping.

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Blog: Designating Genotypes

Introduction to basic terminology that is used in genotyping protocols

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The Why's and When's of Genotyping Your JAX Mice

Have you ever started an experiment with a newly arrived mouse strain, but then had unexpected results? You may have then genotyped the mice and discovered that they were not the genotype that you expected. This can be a frustrating experience that wastes time and causes unnecessary extra work. This is just one example of a scenario where genotyping your mice is important.

An essential step in mouse breeding is genotyping your mice to ensure that they have the expected genotype. The genotype for a specified gene in a mouse can be homozygous, heterozygous, wild type, and sometimes hemizygous (such as X-linked genes or transgenes). You may even have multiple genes with multiple genotypes in one mouse. The genotype of your mouse determines the phenotype. Therefore, a homozygous mouse will have different characteristics than a heterozygous mouse. For this reason, it is important to routinely genotype your mice to maintain consistency with your mouse colonies.

There are three scenarios when you should genotype your mice.

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